Liu, Shuai, Liu, Shuai, Ma, Pengchen, Zhang, Lu, Shen, Shenyu, Miao, Hong-Jie, Liu, Le, Houk, KN, Duan, Xin-Hua, Guo, Li-Na, Liu, Shuai, Liu, Shuai, Ma, Pengchen, Zhang, Lu, Shen, Shenyu, Miao, Hong-Jie, Liu, Le, Houk, KN, Duan, Xin-Hua, and Guo, Li-Na
An efficient alkoxyl radical-triggered ring expansion/cross-coupling cascade was developed under cheap metal catalysis. Through the metal-catalyzed radical relay strategy, a wide range of medium-sized lactones (9-11 membered) and macrolactones (12, 13, 15, 18, and 19-membered) were constructed in moderate to good yields, along with diverse functional groups including CN, N3, SCN, and X groups installed concurrently. Density functional theory (DFT) calculations revealed that reductive elimination of the cycloalkyl-Cu(iii) species is a more favorable reaction pathway for the cross-coupling step. Based on the results of experiments and DFT, a Cu(i)/Cu(ii)/Cu(iii) catalytic cycle is proposed for this tandem reaction.